In modem communications technology it has become common practice to provide two related but separate network infrastructures: a transmission network for carrying end-user data traffic, and a signalling network for controlling operation of the transmission network in accordance with control signals transferred through the signalling network. In practice such signalling networks comprise high-speed computers interconnected by signalling links; computer programs control the computers to provide a set of operational and signalling functions in accordance with a standardized protocol. One example of such a signalling protocol is the afore-mentioned Signalling System No. 7 (SS7) which is being extensively deployed for control of telephone and other data transmission networks. An SS7 network basically comprises various types of signalling points, namely, signalling end points (SEPs) and signalling transfer points (STPs) interconnected by signalling links, the SEPs being associated for example with respective service switching points (SSPs) of the transmission network, and service control points (SCPs).
The large size and complexity of the transmission network entails a correspondingly large and complex signalling network, controlled by very sophisticated computer programs. The complexity of signalling networks is increased by the need to provide redundancy to ensure that failure of a single component of the network does not cause failure of the entire network, and thus of the associated transmission network. Thus, for example, it is common in SS7 networks to provide each SSP or SCP with at least two signalling links to respective members of a pair of geographically-separated STPs.
In order to be able to carry out independent monitoring of the signalling network, monitor probes may be temporarily or permanently installed on one or more links to monitor messages flowing on the link or links. By monitoring these messages it is possible to gain an insight into the behaviour of the network and to detect faults. One example of a monitor probe is the Hewlett-Packard 37900B Signalling Test Set.
When a monitor probe is permanently or semi-permanently installed on a link, generally provision is made to have the probe send the results of its monitoring operations automatically to a remote management station; this station may also be able to control the probe to change the focus of its monitoring activities. Of course, for the results coming from a probe to be useful to the management station, the location of the probe, in terms of the absolute identity of the link on which it is installed, must be made known to the management station. This is generally done by having the installing technician communicate this information to the management station. This can take a considerable time and is prone to errors.
It is an object of the invention to facilitate the identification of the link on which a monitor probe is installed.